Long-standing Italian restaurant Calici is understood to have closed suddenly late last year after around four years' trading.
Caldesi Belsize joins Caldesi In Marylebone, the more high-end Caldesi In Campagna in Bray and two cooking schools (one in Bray and another in London’s Gerrard’s Cross).
The new restaurant will have 100-covers and - in a departure for the group - will major on dishes that are designed to be shared.
The Belsize Lane restaurant is currently being refurbished and is expected to launch towards the end of February.
Originally from Tuscany, Caldesi launched his first UK restaurant in 2002 on Marylebone Lane, following up with Caldesi In Campagna in 2007.
He and his wife Katie have published numerous cookbooks and also featured in the BBC2 series Return to Tuscany.